The "Buddha entering Nirvana" (nehanzoo) is a kind of nadebotoke 撫で仏 and people come to touch and rub him on the part where their own pain is felt. Some got better and now send a futon cover for the statue. The head priest uses all the covers from so many people, a different every day sometimes, to keet the buddha from cold in winter and heat in summer.
If it is covered, you just turn away the futon and rub the statue at the place of your pain.
You can see his neck is quite cleanly rubbed.
Usually Binzurusama is the rubbed one, a Shaka lying down to be rubbed is very seldom, maybe the only one in Japan. But it is heartwarming to see people flock around him with their sincere wish to get better.

Anao-ji is the 21st temple on the Saigoku Kannon pilgrimage.
In 962 the priest at the temple was shot by a local samurai. When the warrior entered the temple to steal the rich altar-fittings he found the statue of Kannon pierced with an arrow and bleeding from her breast. The samurai repented and went on to fund many of the temple's works. His grave is in the temple grounds.source : www.taleofgenji.org